Electrical Characterisation of Shallow Pre-Amorphised +n junctions in silicon

1987 ◽  
Vol 104 ◽  
Author(s):  
S. D. Brotherton ◽  
J. R. Ayres ◽  
J. B. Clegg ◽  
B. J. Goldsmith
Keyword(s):  
Leakage Current ◽  
Point Defects ◽  
Solid Phase ◽  
Deep Level ◽  
Dislocation Loops ◽  
Implantation Energy ◽  
Excess Silicon ◽  
Epitaxial Regrowth ◽  
High Concentrations

ABSTRACTAn examination of Si+ pre-amorphised p+n structures as a function of Si+ implantation energy and solid phase epitaxial regrowth temperature has revealed three different classes of defect all of which may influence the characteristics of the junction. They are point defects responsible for high concentrations of deep level donors, and interstitial dislocation loops both causing leakage current degradation, and excess silicon interstitials leading to enhanced junction movement.

Rapid Thermal Annealing of Ion-Implanted Silicon and Gallium Arsenide

1983 ◽  
Vol 23 ◽  
Author(s):  
J. Narayan
Keyword(s):  
Gallium Arsenide ◽  
Free Surface ◽  
Electrical Properties ◽  
Point Defects ◽  
Solid Phase ◽  
Bulk Diffusion ◽  
Dislocation Loops ◽  
Enhanced Diffusion ◽  
Implantation Damage ◽  
Complete Annealing

ABSTRACTWe have investigated the annealing of ion implantation damage (in the form of amorphous layers and/or the layers containing only dislocation loops) in silicon and gallium arsenide. The annealing of amorphous layers occurs by solid-phase-epitaxial growth and that of dislocation loops involves primarily loop-coalescence as a result of conservative climb and glide processes. The annealing of disolated loops occurs primarily by a bulk diffusion process. Almost a “complete” annealing of displacement damage is possible for shallow implants provided loop–coalescence does not lead to the formation of cross–grid of dislocations. For deep implants, the free surface cannot provide an effective sink for defects as in the case of shallow implants. Dopant profiles can be controlled to less than 1000 Å in layers having good electrical properties. The enhanced diffusion of dopants is observed probably due to entrapment of point defects in the annealed regions.

CW Laser Induced Deep Level Defects in Virgin Silicon.

1981 ◽  
Vol 4 ◽  
Author(s):  
A. Chantre ◽  
M. Kechouane ◽  
D. Bois
Keyword(s):  
High Temperature ◽  
Point Defects ◽  
Deep Level Transient Spectroscopy ◽  
Solid Phase ◽  
Deep Level ◽  
Deep Levels ◽  
Cw Laser ◽  
Temperature State ◽  
Transient Spectroscopy ◽  
Induced Defects

ABSTRACTDeep Level Transient Spectroscopy has been used to investigate cw laser induced defects in virgin silicon. Two main regimes have been found. In the solid phase regime, two well defined deep levels at Ec−0.19 eV and Ec−0.45 eV are observed. This point defect introduction is proposed to be involved in the degradation of ion-implanted cw laser annealed junctions. The mechanism leading to point defects generation is likely to involve trapping of in–diffused vacancies, quenched–in from the high temperature state. In the slip lines or melt regimes, additionnal deep levels are detected, which are ascribed to dislocations.

Supersaturated Substitutional Solid Solution after Solid Phase Epitaxial Regrowth by Incoherent Light Scanning.

1981 ◽  
Vol 4 ◽  
Author(s):  
L. Pedulli ◽  
L. Correra
Keyword(s):  
Solid Phase ◽  
Substitutional Solid Solution ◽  
Dislocation Loops ◽  
Incoherent Light ◽  
Dopant Activation ◽  
Epitaxial Regrowth ◽  
Electron Microscopy Analysis ◽  
Residual Damage ◽  
Microscopy Analysis ◽  
Minority Carriers

ABSTRACTSupersaturated substitutional solid solutions of 2×101531P+ /cm2 implanted at 10 keV in (100) Silicon were obtained after solid phase epitaxial regrowth using a scanning beam of incoherent light. The main results are: a) the maximum P+ concentration exceeds of about 5 times the maximum solid solubility at the temperature reached by the sample; b) the carrier concentration profile shows a complete dopant activation without diffusion of the implanted ions; c) an improvement of minority carriers diffusion length in the bulk is often observed; d) the values of carrier mobilities are similar to those obtained after liquid phase regrowth by pulsed ruby laser; e) a very good recovery of the damage is obtained: Rutherford backscattering spectra show that the dechanneling fraction is very close to the value of virgin samples and Trasmission Electron Microscopy analysis shows that the residual damage consists of dislocation loops of about 30 Å diameter confined in a region at about 500 Å depth.

Characterization of Si MBE Layers Doped in Situ by As Ion Beams

1987 ◽  
Vol 102 ◽  
Author(s):  
Max L. Swanson ◽  
N.R. Parikh ◽  
T.E. Jackman ◽  
D.C. Houghton ◽  
M.W. Denhoff
Keyword(s):  
Structural Damage ◽  
Electrical Activation ◽  
Dislocation Loops ◽  
Electrical Measurements ◽  
Implantation Energy ◽  
Mbe Growth ◽  
Transmission Electron ◽  
High Concentrations

ABSTRACTTo achieve high concentrations and electrical activation of As in Si without subsequent annealing, 500-3000 eV As + ions were implanted during MBE growth of Si at 450-840°C. The epitaxial layers were characterized by Rutherford backscattering/channeling, transmission electron microscopy, secondary ion mald spectroscopy, and electrical measurements. Samples containing 1.2×1020 As cm-3 grown at 700°C showed little damage, high As substitutionality and high electrical activation. However, similarly doped layers grown at 460°C showed lower As activation and varying amounts of structural damage. In one case, a band of damage near the Si substrate was observed which persisted even after rapid thermal annealing at 1120°C (10 s); the damage was characterized by a dechanneling step, non-substitutional As atoms and dislocation loops. A sample grown at 460°C with a high implantation energy (3 keV) was highly defected.

Influence of the Temperature of Implantation on the Morphology of Defects in MeV Implanted GaAs.

1989 ◽  
Vol 147 ◽  
Author(s):  
G. Braunstein ◽  
Samuel Chen ◽  
S.-Tong Lee ◽  
G. Rajeswaran.
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Point Defects ◽  
Room Temperature ◽  
Surface Region ◽  
Amorphous Region ◽  
Liquid Nitrogen Temperature ◽  
Dislocation Loops ◽  
Near Surface ◽  
Epitaxial Regrowth

AbstractWe have studied the influence of the temperature of implantation on the morphology of the defects created during 1-MeV implantation of Si into GaAs, using RBS-channeling and TEM. The annealing behavior of the disorder has also been investigated.Implantation at liquid-nitrogen temperature results in the amorphization of the implanted sample for doses of 2×1014 cm−2 and larger. Subsequent rapid thermal annealing at 900°C for 10 seconds leads to partial epitaxial regrowth of the amorphous layer. Depending on the implantation dose, the regrowth can proceed from both the front and back ends of the amorphous region or only from the deep end of the implanted zone. Nucleation and growth of a polycrystalline phase occurs concurrently, limiting the extent of the epitaxial regrowth. After implantation at room temperature and above, two distinct types of residual defects are observed or inferred: point defect complexes and dislocation loops. Most of the point defects disappear after rapid thermal annealing at temperatures ≥ 700°C. The effect of annealing on the dislocation loops depends on the distance from the surface of the sample. Those in the near surface region disappear upon rapid thermal annealing at 700°C, whereas the loops located deeper in the sample grow in size and begin to anneal out only at temperatures in excess of 900°C. Implantation at temperatures of 200 - 300°C results in a large reduction in the number of residual point defects. Subsequent annealing at 900°C leads to a nearly defect-free surface region and, underneath that, a buried band of partial dislocation loops similar to those observed in the samples implanted at room temperature and subsequently annealed.

Boron Activation During Solid Phase Epitaxial Regrowth

2000 ◽  
Vol 610 ◽  
Author(s):  
C. D. Lindfors ◽  
K. S. Jones ◽  
M. E. Law ◽  
D. F. Downey ◽  
R. W. Murto
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Solid Phase ◽  
Dose Range ◽  
Amorphous Layer ◽  
Silicon Wafers ◽  
Dopant Activation ◽  
Epitaxial Regrowth ◽  
High Concentrations ◽  
Secondary Ion ◽  
Resistance Data

AbstractTo continue scaling dimensions of transistors, higher dopant concentration levels are needed for ultra-shallow contacts. Therefore studies of dopant activation have been performed in preamorphized silicon wafers with various boron implant conditions to determine the maximum achievable dopant concentrations after Solid Phase Epitaxial Regrowth (SPER) alone. In the first experiment a silicon piece was preamorphized with a 30 keV, 1×1015 cm−2 and 90 keV, 1×1015 cm−2 Si+ implant followed by a 30 keV, 1×1015 cm−2 B+ implant. Solid phase epitaxial regrowth at 500 °C indicates that boron can be activated at low temperatures. Ultra Low Energy (ULE) implants were studied in the second experiment. Silicon wafers were implanted with 2.5 keV, 1×1015 cm−2 Si+ to amorphize and then B+ was implanted at 0.5 keV in the dose range of 1×1015 to 9×1015 cm−2. Samples were annealed in the temperature range of 500 to 650 °C. High concentrations of boron make it difficult to fully regrow amorphous layers and thus yield marginal electrical properties. Much of the boron remains inactive, particularly at the higher dose implants. In both experiments Variable Angle Spectroscopic Ellipsometry (VASE) is used to measure amorphous layer thickness and Hall effect measures active boron dose. For the first experiment, Secondary Ion Mass Spectrometry (SIMS) data compares chemical dose to active dose during the regrowth process. Sheet resistance data is obtained from a four point probe for the ULE implant experiment.

Effects of Electrically Active Impurities on the Epitaxial Regrowth Rate of Amorphized Silicon and Germanium

1981 ◽  
Vol 10 ◽  
Author(s):  
I. Suni ◽  
G. Göltz ◽  
M.-A. Nicolet ◽  
S. S. Lau
Keyword(s):  
Low Temperature ◽  
Point Defects ◽  
Concentration Level ◽  
Solid Phase ◽  
Surface Layers ◽  
Furnace Annealing ◽  
Epitaxial Regrowth ◽  
Silicon And Germanium ◽  
P Type ◽  
Temperature Furnace

The influence of electrically active n-type (75As) and p-type (11B) impurities on the solid phase epitaxial regrowth of ion-implanted amorphized Si<100> and Ge<100> has been studied for low temperature furnace annealing. Both types of impurity increase the rate of regrowth of both silicon and germanium at a concentration level of 1020 cm−3 . Above this level, 75As retards regrowth in germanium. In compensated surface layers, the regrowth rate slows down to the values observed in self-implanted or intrinsic crystals for both silicon and germanium. The results can be qualitatively explained in terms of electrically induced generation of point defects at the amorphous-crystalline interface.

Study of dislocation loops in Arsenic-Rich as-grown GaAs

1987 ◽  
Vol 45 ◽  
pp. 350-351
Author(s):  
Byung-Teak Lee
Keyword(s):  
Point Defects ◽  
Electronic Devices ◽  
Arsenic Concentration ◽  
Stoichiometric Compound ◽  
Dislocation Loops ◽  
Gaas Crystal ◽  
Ion Milling ◽  
Transmission Electron ◽  
Arsenic Source ◽  
High Arsenic

Grown-in dislocations in GaAs have been a major obstacle in utilizing this material for the potential electronic devices. Although it has been proposed in many reports that supersaturation of point defects can generate dislocation loops in growing crystals and can be a main formation mechanism of grown-in dislocations, there are very few reports on either the observation or the structural analysis of the stoichiometry-generated loops. In this work, dislocation loops in an arsenic-rich GaAs crystal have been studied by transmission electron microscopy.The single crystal with high arsenic concentration was grown using the Horizontal Bridgman method. The arsenic source temperature during the crystal growth was about 630°C whereas 617±1°C is normally believed to be optimum one to grow a stoichiometric compound. Samples with various orientations were prepared either by chemical thinning or ion milling and examined in both a JEOL JEM 200CX and a Siemens Elmiskop 102.

Contrast From Point Defects in The Infinitesimal Approximation

1980 ◽  
Vol 38 ◽  
pp. 350-351
Author(s):  
L. J. Sykes ◽  
J. J. Hren
Keyword(s):  
Electron Microscope ◽  
Point Defects ◽  
Broad Class ◽  
Stacking Fault ◽  
Crystalline Solids ◽  
Dislocation Loops ◽  
Analytical Expression ◽  
Stacking Fault Tetrahedra

In electron microscope studies of crystalline solids there is a broad class of very small objects which are imaged primarily by strain contrast. Typical examples include: dislocation loops, precipitates, stacking fault tetrahedra and voids. Such objects are very difficult to identify and measure because of the sensitivity of their image to a host of variables and a similarity in their images. A number of attempts have been made to publish contrast rules to help the microscopist sort out certain subclasses of such defects. For example, Ashby and Brown (1963) described semi-quantitative rules to understand small precipitates. Eyre et al. (1979) published a catalog of images for BCC dislocation loops. Katerbau (1976) described an analytical expression to help understand contrast from small defects. There are other publications as well.

scholarly journals Fe3O4@C Nanoparticles Synthesized by In Situ Solid-Phase Method for Removal of Methylene Blue

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 330
Author(s):  
Hengli Xiang ◽  
Genkuan Ren ◽  
Yanjun Zhong ◽  
Dehua Xu ◽  
Zhiye Zhang ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Solid Phase ◽  
Raw Materials ◽  
Phase Method ◽  
Maximum Adsorption Capacity ◽  
High Catalytic Activity ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
High Concentrations

Fe3O4@C nanoparticles were prepared by an in situ, solid-phase reaction, without any precursor, using FeSO4, FeS2, and PVP K30 as raw materials. The nanoparticles were utilized to decolorize high concentrations methylene blue (MB). The results indicated that the maximum adsorption capacity of the Fe3O4@C nanoparticles was 18.52 mg/g, and that the adsorption process was exothermic. Additionally, by employing H2O2 as the initiator of a Fenton-like reaction, the removal efficiency of 100 mg/L MB reached ~99% with Fe3O4@C nanoparticles, while that of MB was only ~34% using pure Fe3O4 nanoparticles. The mechanism of H2O2 activated on the Fe3O4@C nanoparticles and the possible degradation pathways of MB are discussed. The Fe3O4@C nanoparticles retained high catalytic activity after five usage cycles. This work describes a facile method for producing Fe3O4@C nanoparticles with excellent catalytic reactivity, and therefore, represents a promising approach for the industrial production of Fe3O4@C nanoparticles for the treatment of high concentrations of dyes in wastewater.

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